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Numerous techniques of water filtration are in use today, most of which involve the use of sand as the porous media. After A preliminary research literature review revealed a lack dearth of information on foam filtration, our . Uur team has decided to focus on investigating the actual filtering capacity of a polyurethane foam material as opposed to the traditional method of sand filtration. With proper implementation, a foam filter could reduce the amount of water that is wasted during the backwash cycle of a traditional sand filter. A foam filter could also potentially require less area, and be less expensive to build than a traditional sand filter. However, a foam filtration unit will also require a tight seal with all of the edges of the tank, in order to avoid preferential flow paths which will result in unfiltered water. In addition, a foam filter will likely require manual maintenance by the plant operator.
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An alternative to using the foam simply as a flat sheet which water is filtered through is to design a hybrid upflow filter, which uses small pieces of the foam as the filtering material, as opposed to the traditional upflow sand filter. This idea is based on the technique outlined in this article, Water Filtration- Advantages of Fabric Media